FIELD: recovery of water wells. SUBSTANCE: method is designed for recovery of water well located in underground structures of subway type which have lost their sealing due to corrosion of their casing string. The method includes drilling of new well directly from underground structure alongside the casing string of emergency well. Drilling is carried out with stopping short of water-bearing horizon. Supplied to well is cryogenic fluid in the form, mainly, of liquid nitrogen. Under action of subzero temperature of nitrogen, water is frozen at level of upper part of strainer of emergency well. Ice plug is formed in process of freezing. New casing string is installed inside old casing string. Interpipe space and well head are sealed with cement mortar. Ice plug is removed from well strainer by natural thawing out or by supply of hot water instead of cryogenic fluid. EFFECT: higher safety in major repairs of water wells of underground structures, excluded water drawdown work. 1 dwg
